Skip to contentSkip to conversation

USB: iowarrior: fix missing endpoint sanity checks

PATCH New Johan Hovold 1 participant 3 messages Mar 7, 2017 – Mar 8, 2017

Subsystems (2)
Stable branch USB
lore
Share & tools
lore

Johan Hovold

author
#0 lore raw

cover USB: iowarrior: fix missing endpoint sanity checks

These patches add the missing endpoint sanity checks to probe that are needed to prevent a couple of NULL-derefs which could be trigger by a malicious device.

Johan

Johan Hovold (2):
USB: iowarrior: fix NULL-deref at probe
USB: iowarrior: fix NULL-deref in write

 drivers/usb/misc/iowarrior.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)
Signature · 1 line
2.12.0
author
#1 lore raw

PATCH 1/2 USB: iowarrior: fix NULL-deref at probe

Make sure to check for the required interrupt-in endpoint to avoid dereferencing a NULL-pointer should a malicious device lack such an endpoint.

Note that a fairly recent change purported to fix this issue, but added an insufficient test on the number of endpoints only, a test which can now be removed.

Fixes 4ec0ef3a8212 ("USB: iowarrior: fix oops with malicious USB

descriptors")

Fixes 946b960d13c1 ("USB: add driver for iowarrior devices.")
Cc stable <[email protected]> # 2.6.21
Signed-off-by Johan Hovold <[email protected]>
---
 drivers/usb/misc/iowarrior.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)
drivers/usb/misc/iowarrior.c +7 -6
index 095778ff984d..3ad058cbe6ca 100644
@@ -781,12 +781,6 @@ static int iowarrior_probe(struct usb_interface *interface,
 	iface_desc = interface->cur_altsetting;
 	dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
 
-	if (iface_desc->desc.bNumEndpoints < 1) {
-		dev_err(&interface->dev, "Invalid number of endpoints\n");
-		retval = -EINVAL;
-		goto error;
-	}
-
 	/* set up the endpoint information */
 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 		endpoint = &iface_desc->endpoint[i].desc;

@@ -797,6 +791,13 @@ static int iowarrior_probe(struct usb_interface *interface,
 			/* this one will match for the IOWarrior56 only */
 			dev->int_out_endpoint = endpoint;
 	}
+
+	if (!dev->int_in_endpoint) {
+		dev_err(&interface->dev, "no interrupt-in endpoint found\n");
+		retval = -ENODEV;
+		goto error;
+	}
+
 	/* we have to check the report_size often, so remember it in the endianness suitable for our machine */
 	dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
 	if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
Signature · 1 line
2.12.0
author
#2 lore raw

PATCH 2/2 USB: iowarrior: fix NULL-deref in write

In reply to Johan Hovold

Make sure to verify that we have the required interrupt-out endpoint for IOWarrior56 devices to avoid dereferencing a NULL-pointer in write should a malicious device lack such an endpoint.

Fixes 946b960d13c1 ("USB: add driver for iowarrior devices.")
Cc stable <[email protected]> # 2.6.21
Signed-off-by Johan Hovold <[email protected]>
---
 drivers/usb/misc/iowarrior.c | 8 ++++++++
 1 file changed, 8 insertions(+)
drivers/usb/misc/iowarrior.c +8 -0
index 3ad058cbe6ca..37c63cb39714 100644
@@ -798,6 +798,14 @@ static int iowarrior_probe(struct usb_interface *interface,
 		goto error;
 	}
 
+	if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) {
+		if (!dev->int_out_endpoint) {
+			dev_err(&interface->dev, "no interrupt-out endpoint found\n");
+			retval = -ENODEV;
+			goto error;
+		}
+	}
+
 	/* we have to check the report_size often, so remember it in the endianness suitable for our machine */
 	dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
 	if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&
Signature · 1 line
2.12.0